n = int(input())
d = input()
a = [int(x) for x in d.split()]
a1 = a.count(1)
a2 = a.count(2)
if a1==0 or a2==0:
print(d)
else:
l = [2,1]+[2 for i in range(a2-1)]+[1 for i in range(a1-1)]
print(" ".join(map(str,l)))
#define ll long long
#define MAXN 200010
#define INF 0x3f3f3f3f
#include <bits/stdc++.h>
using namespace std;
int main(){
#ifdef _DEBUG
freopen("in.txt","r",stdin);
//freopen("out.txt","w",stdout);
#endif
#define int ll
ios::sync_with_stdio(false);
cin.tie(0);
int n;
cin >> n;
int one = 0;
for (int i = 0; i < n; ++i) {
int x;
cin >> x;
if (x == 1) {
++one;
}
}
if (one < n) {
cout << "2 ";
--n;
}
if (one) {
cout << "1 ";
--n;
--one;
}
for (int i = 0; i < n - one; ++i) {
cout << "2 ";
}
for (int i = 0; i < one; ++i) {
cout << "1 ";
}
cout << endl;
return 0;
}742A - Arpa’s hard exam and Mehrdad’s naive cheat | 1492A - Three swimmers |
1360E - Polygon | 1517D - Explorer Space |
1230B - Ania and Minimizing | 1201A - Important Exam |
676A - Nicholas and Permutation | 431A - Black Square |
474B - Worms | 987B - High School Become Human |
1223A - CME | 1658B - Marin and Anti-coprime Permutation |
14B - Young Photographer | 143A - Help Vasilisa the Wise 2 |
320A - Magic Numbers | 1658A - Marin and Photoshoot |
514A - Chewbaсca and Number | 382A - Ksenia and Pan Scales |
734B - Anton and Digits | 1080A - Petya and Origami |
1642D - Repetitions Decoding | 1440A - Buy the String |
1658F - Juju and Binary String | 478A - Initial Bet |
981A - Antipalindrome | 365A - Good Number |
1204B - Mislove Has Lost an Array | 1409D - Decrease the Sum of Digits |
1476E - Pattern Matching | 1107A - Digits Sequence Dividing |